This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Small-angle X-ray Scattering of a protein complex formed by VGCC b4c and chromo shadow domain of HP1 A short splicing form of voltage-gated chalcium channel (VGCC) beta 4 subunit interacts with a nuclear protein Heterochromotin Protein 1 (HP1) and regulates gene silencing. The complex formation between the truncated VGCC b4 and chromo shadow domain (CSD) of HP1 has been confirmed in vitro by pull down experiment, ITC and NMR spectroscopy in Dr. Bill Horne[unreadable][unreadable]"s group in Vet school. Dr. Horne (PI) and his postdoc Dr. Xingfu Xu want to determine the molecular envelope of this complex using Small-angle X-ray scattering and validate the structure model derived from NMR docking.